Printing of textiles



United States Patent 2,992,878 PRINTING 0F TEXTILES Paul A. Studer,Millburn, NJ., nssignor to Celanese Corporation of America, New York,N.Y., a corporation of Delaware No Drawing. Filed Aug. 24, 1955, Ser.No. 530,427 2 Claims. (Cl. 8-63) This invention relates to printing andrelates more particularly to the printing of a textile material having abasis of a cellulose ester of very low hydroxyl content.

A method of printing textile materials comprising cellulose esters oflow hydroxyl content involves the deposition of a printing paste on thetextile material, followed by heat treatment of the textile material tocause penetration of the coloring maerial of said paste into saidcellulose ester and to cause, at the same time, an improvement in thecolor fastness and in the physical properties of the textile material.This heat treatment effects an improvement in the safe ironing point ofthe textile material and also improves its resistance to glazing, itsresistance to shrinkage on pressing with moist steam, its ability to bepleated permanently and its resistance to mussing and wrinkling onlaundering. However, when the procedures conventionally recommended forprinting textile material comprising cellulose esters of high hydroxylcontent with basic or dispersed dyestuffs are employed in the printingof textile material comprising cellulose esters of low hydroxyl content,then the desired level of improvement in the color fastness and inphysical properties is not achieved. Moreover, there is an insufiicientcolor l wyield and a poor reproducibility of the hue of the dyed textilematerial, particularly in mixed shades.

It is therefore an object of this invention to provide a novel processfor the printing of textile materials having a basis of a celluloseester of low hydroxyl content which will be free from the foregoing andother defects.

Another objects of this invention is the production of a new printingpaste.

Other objects of this invention will be apparent from the followingdetailed description and claims. In this description and claims allproportions are by weight unless otherwise indicated.

In accordance with one aspect of this invention there is applied to atextile materials having a basis of a cellulose ester of low hydroxylcontent an aqueous printing paste containing a dispersed celluloseacetate dyestufli, and a minor amount of a phenyl compound selected fromthe group consisting of p-phenoxy ethanol, a-phenyl ethanol (phenylmethyl carbinol), and p-phenyl ethanol. The printing paste is then driedon the textile material and the material is thereafter given a heattreatment to cause the dye to penetrate into the cellulose ester.

The cellulose esters of low hydroxyl content employed in the process ofthis invention contain not more than 0.29, preferably 0 to 0.12,alcoholic hydroxyl groups per anhydroglucose unit in the cellulosemolecules thereof. Best results are obtained by the use of celluloseacetate of very high acetyl value, e.g. an acetyl value of preferably 61to 62.5%, calculated as combined acetic acid. However, other organicacid esters of cellulose of low hydroxyl content may be employed.Examples of such other esters are cellulose propionatc, cellulosebutyrate, cellulose acetate-propionate, cellulose acetate-butyrate andcellulose acetateforrnate.

This invention is applicable generally to printing the textile materialwith all dispersed and basic dyestuffs that show an affinity for textilematerial comprising cellulose esters of low hydroxy-l content whenapplied to said material and heat treated. However, when the heattreatment is carried out using dry heat, care should be taken to avoidthe use of those dyestulfs that will sublime under the conditions of theheat treatment in order to retain the sharpness of the printed design.When the heat treatment is carried out using steam, no such precautionsneed be taken. After heat treatment, the printed textile material showslittle or no color loss and substantially no staining when washed, evenat temperatures as high as 160 F. Because of the absence of staining,the textile material is suited for commercial use even when there issome washdown of the dyestuflis.

Examples of suitable dispersed dyestuffs are such compounds at2-nitro-4-sulfonanilido diphenylamine, 4'- ethoxy 2 nitrodiphenylaminefl-hydroxypropylsulfonamide, 4mitro-2-methoxyphenyl azo4'-bis(beta-hydroxyethyl) amino-2'-acetylaminobenzene, 4nitro-2-methylsulfonephenyl azo4'-(N-beta-hydroxy-ethyl-N-difiuoroethyl) aminobenzene,4-nitro-2-chlorophenyl azo 4'-bis- (beta-hydroxy-ethyl)a.rnino-2'-methylbenzene, l hydroxyethylamino-4-hydroxy ethylamino 5hydroxy 8 hydroxy anthraquinone, 4-nitrophenyl azo 4--di-,8-hydroxyethylamino2'-acetaminobenzene, a mixture of 1,4 di-(hydroxy-ethylamino)-5,8-dihydroxy anthraquinone and 1-amino-4-anilidoanthraquinone, 1,5-dihydroxy-8-nitro- 4-(meta-alpha-hydroxycthyl)anilido anthraquinone, 1,8 dihydroxy 4 (para-beta-hydroxyethyl):anilido-S-nitro anthraquinone, l-amino-4-anilido anthraquinone,2-nitro- 4-sulfonamido diphenylamine, p-nitrophenyl azo diethyl aniline,l-amino-4-hydroxy anthraquinone and 2,4-dinitro-6-chlorophenyl azo4'-bis (hydroxyethyl) amino- 2'-acetylamino-5'-methoxy benzene. Thesedyestuffs are usually sold in the form of mixtures of a dispersingagent, such as sodium lignosulfonate or the sodium salt offormaldahyde-naphthalene sulfonic acid condensation prod net, with theactual dye material, and usually contain about 30 to 45% of the actualdye material.

Commercial dispersed dyestuffs include Eastman Blue GLF, Lenra Blue RLS,Interchem Triacetate Blue GSF, Cibacete Blue GLF, Latyl Blue FL,Celliton Blue LAFR, Nacelan Blue KLF, Latyl Blue BG, Eastone Red GLF,Interchem Triacetate Red GSF, Interchem Triacetate Scarlet GSF, CellitonRed GGLL, Eastone Fast Red ZBGLF, Eastone Fast Pink 3BGLF, Cibacete RedGGF, Celliton Fast Red 6DAC, Celanthrene Violet BGF, Eastman VioletSRGLF, Nacelan Red 2G, Lenra Yellow CW, Inter-chem Triacetate YellowHDLF-40, Cellitorr Fast Yellow GGLL, Latyl Yellow YL, Eastone FastYellow ZRGLF, Artisil Yellow RCGFL, Cibacete Yellow'GWN and Nacelan FastYellow KAL.

Basic dyestulfs that may be employed in carrying out the process of thisinvention include Methyl violet, Capri blue, Du Pont Basic Blue OB, DuPont Basic Yellow OR, Du Pont Brilliant Green, Rhodamine B, CalcozineRed G and.Calcozine Red Y.

The major constituent of the printing paste of this invention is water,the proportion thereof being generally or higher.

It will be apparent that the amount of dye used in the printing pastewill vary in accordance with the depth of color desired. Suitableproportions are, for example, up to 10%, by weight, based on weight ofprinting paste.

As is conventional in textile printing, a thickening agent is present inthe printing paste. Generally, all types of thickening agents commonlyused in textile printing are suitable for use in the printing process ofthis invention when the heat treatment of the printed textile materialis achieved through the use of steam. When the heat treatment isachieved through the use of dry heat, it is advantageous to usethickening agents that remain easily water soluble after being subjectedto dry heat so that they may be readily washed from the textile materialafter the heat treatment process. Thus, there may be used in this lattercase thickening agents such as alginates (e.g. the alginate sold underthe name Keltex") and modified locust bean gum (e.g. the modified gumsold under the name Itagum R) are very suitable. Materials such asBritish gum starches, gum karaya, gum tragacanth and gum arabic are muchless desirable for this purpose. The amount of thickening agent used issufficient to impart to the mixture the known relatively high viscosityof a printing paste. A suitable concentration of thickener is, forexample, 2 to 8%, by dry weight, based on weight of printing paste,depending on the type and method of application.

The amount of B-phenoxyethanol, a-phenyl ethanol, or p-phenyl ethanolpresent in the printing paste should be greater than the solubilitythereof in water, so that at least a portion of this compound is in awater-immiscible phase in the paste. Smaller proportions, e.g. less than2%, based on the total weight of printing paste, cause only a slightimprovement. Optimum results with respect to color yield andreproducibility of shade are obtained by employing at least about 4%.Amounts larger than 8% of these compounds, e.g. 12 or 14%, are notrecommended since they are economically wasteful in that they do notcause a significant further improvement in the properties of the printedmaterial. If desired, the printing paste may comprise a mixture of anytwo, or all three, of these compounds.

Since some of the dyestuffs used in the practice of this invention tendto fade when applied to cellulose esters of low hydroxyl content andexposed to atmospheres containing ozone or nitrous oxide, it isdesirable to have present a material which inhibits such fading. Anexample of suitable inhibitors is the formaldehyde-bisulfite additionproduct of diphenylimidazolidine sold under the name Anti-Fume DEN. Theinhibitor is preferably incorporated into the printing paste, a suitableconcentration of inhibitor being 1 to 3%, based on weight of printingpaste.

Any convenient process maybe used for the application of the printingpaste of this invention to the textile material having a basis of acellulose ester of low hydroxyl content. Thus, the paste may be appliedby the usual silk screen or roller printing methods. Different colors ofpaste may be applied to different areas of the fabric with or withoutoverlapping. Conveniently, the paste is applied at room temperature.However, the paste may be printed onto the textile material at anelevated temperature, e.g. 40 to 70 C., if desired. For best results,the textile material should be freed of foreign materials, as bythoroughscouring, or scouring and bleaching before the paste is applied. Afterthe paste has been applied, the printed fabric is dried, either at roomtemperature or at elevated temperature, e.g. 50 to 150 C. depending onexposure time.

During the printing and drying steps some of the dye is absorbed intothe cellulose ester textile material, but a large part of the dye, forexample 50 to 80% thereof, depending on the solubility of the dye in theprinting paste and on the printing temperature, remains in the paste onthe surface of the textile material.

After the printing paste hasbeen applied to the textile material anddried thereon, the textile material is given a heat-setting treatment,which serves to increase the color value, to improve the penetration ofthe dye into the cellulose ester which increases the wash-fastness,resistance to gas-fading, fastness to dry cleaning, crock fastness,resistance to ozone-fading and resistance to crocking of the dyedmaterial. Heat-setting also effects an improvement in the physicalproperties of the textile material. Thus, it effects an improvement inthe safe ironing temperature, the ability of the material to be pleatedpermanently, its resistance to glazing, its resistance to shrinkage onpressing with moist steam, its resistance to mussing or wrinkling onlaundering, its resistance to degradation or weakening on exposure toelevated temperatures for long periods of time and its resistance todegradation in sunlight. For example, heat-setting of a fabric ofcellulose acetate of low hydroxyl content raises its safe ironingtemperature by at least about C., e.g. to 220 C. or'240" C. or higher.Heat-setting generally-results in an increase in the crystallinity andcrystalline order of the cellulose ester material.

The conditions of heat-setting will depend somewhat on the particulartextile material being treated, for example, on its weight andconstruction. In general, when dry heat is used, as when the textilematerial is passed through a hot air heater, an infra-red heater or incontact with heated rollers or drums, temperatures of 190 C. or aboveare employed. Preferably, the material is heated to a temperature ofabout 220 to 235 C. for about 10 to 30 seconds. With lower temperatures,e.g. 190 C., the heating time is considerably longer, for example 5 to10 minutes. Still lower heat-setting temperatures may be employed whenthe heat is applied by means of saturated steam under a pressure of, forexample, 5- to 50 pounds per square inch gauge.

'If desired, the drying step need not be carried out separately, but mayconstitute the first stage of the heatsetting operation when the heatsetting is achieved through the use of dry heat.

This invention may also beemployed in the coloring of textile materialsof cellulose esters of low hydroxyl content which have been previouslyheat-set. An example i of such a material is a fabric of celluloseacetate of low hydroxyl content which has been heat-set sufficiently toraise its safe ironing temperature to at least 220 C., e.g. to about 240C. or higher. Such heat-set materials are even more resistant tocoloring by ordinary methods than the materials which have not beenheat-set. However, by the use of the. present invention these materialscan be colored in full, crock-resistant, wash-fast shades. For example,the process of this invention may be applied in the printing of tricotmaterial which has been previously 5 stabilized by heat-setting withsaturated steam in an autoclave.

After heat-setting there remains on the surface of the printed materiala layer of the thickening agent used in the printing paste together witha very small amount of loosely adherent dyestufl. It is best to removethese materials by thorough scouring.

Any of the usual finishing materials for textile materials having abasis of cellulose esters of low-hydroxyl content may be applied afterthe heat-setting operation.

For example, there may be employed the finishing agents listed in thecopending application of Salvin et al., Ser. No. 472,758. In some cases,as, for, example, in the case of the silicone finishes, the finish maybe applied to the textile material before the printing and heattreatment thereof.

The use of the p-phenoxy ethanol, a-phenyl ethanol or p-phenyl ethanolin the printing paste results in sharp prints in which the color value,color fastness, general appearance and reproducibility are excellent,with the best results being obtained by the use of the p-phenoxy ethanolor the a-phenyl ethanol. In contrast, the desired results are notobtained by the use of such closely related solvents for the dyestuffsas fl-phenoxyethoxy ethanol, butoxyethoxy ethanol and benzyl alcohol, orby the-use of such other dyestulf solvents as triethyl phosphate,tripropyl phosphate and propylene carbonate.

The following examples are given to illustrate this invention further.

Example I is prepared by first thoroughly pasting the dyestufi and thegas-fading inhibitor in cold water, then dispersing them in hot water,thereafter adding the resultant disto thoroughly disperse or dissolvethe dye. The amount and character of the dyestufi depends on the shadedesired. Thus, for a dark gray shade, the printing paste contains 0.4%of Eastman Blue GLF, 0.12% of Eastone Red GLF and 0.2% of InterchemicalYellow HDLF-40, while for a beige shade the proportions of these threedyestuffs are 0.4%, 0.2% and 0.2% respectively. A grass green shade isproduced when the printing paste contains 1.5% of Latyl Blue BG and 1.5%of Interchemical Yellow HDLF-40. Thereafer the fabric is dried at 70 C.for minutes, then preheated for a short-time at 120 C. and heat-set at230 C. (fabric temperature) for seconds. The fabric is then washedthoroughly with an aqueous solution of 1 gram per liter of soap and 1gram per liter of Calgon for 15 minutes at 60 C. A sharp, wash-fastprint of excellent appearance is obtained.

Example II Example I is repeated, using p-phenoxy ethanol in place ofthe a-phenyl ethanol. The results are substantially identical with thoseof Example I.

Example III Example II is repeated except that 1.5 parts of Itagum R-10(a modified locust bean gum) are substituted for each part of Keltex.The results are substantially identical with those of Example I.

It is to be understood that the foregoing detailed description is merelygiven by way of illustration and that many variations may be madetherein without departing from the spirit of my invention.

Having described my invention, what I desire to secure by Letters Patentis:

l. A printing paste for textile material comprising a cellulose acetatedyestuff, 2 to 8% of a-phenyl ethanol and, a thickener which remainswater-soluble on heat treatment at 235 C. for 30 seconds.

2. Process for the coloring of textiles, comprising printing onto atextile fabric of cellulose acetate of at least 61% acetyl value,calculated as combined acetic acid, a printing paste comprising acellulose acetate dyestutt, 4 to 8% of a-phenyl ethanol, said printingpaste containing a thickener which remains water-soluble on heattreatment at 235 C. for 30 seconds, then subjecting said textilematerial to a heat-setting treatment to increase the penetration of saiddyestuif into said cellulose acetate, and washing said material toremove said thickener after the heat-setting.

References Cited in the file of this patent UNITED STATES PATENTS1,968,856 Rivat Aug. 7, 1934 2,049,657 McQueen Aug. 4, 1936 2,080,254Dreyfus May 11, 1937 2,274,751 Sowter Mar. 3, 1942 2,524,811 KoberleinOct. 10, 1950 OTHER REFERENCES Textile Manufacturer for February 1955pp. 71 and 72.

1. A PRINTING PASTE FOR TEXTILE MATERIAL COMPRISING A CELLULOSE ACETATE DYESTUFF, 2 TO 8% OF A-PHENYL ETHANOL AND, A THICKENER WHICH REMAINS WATER-SOLUBLE ON HEAT TREATMENT AT 235*C. FOR 30 SECONDS.
 2. PROCESS FOR THE COLORING OF TEXTILES, COMPRISING PRINTING ONTO A TEXTILE FABRIC OF CELLULOSE ACETATE OF AT LEAST 61% ACETYL VALUE, CALCULATED AS COMBINED ACETIC ACID, A PRINTING PASTE COMPRISING A CELLULOSE ACETATE DYESTUFF 4 TO 8% OF A-PHENYL ETHANOL, SAID PRINTING PASTE CONTAINING A THICKENER WHICH REMAINS WATER-SOLUBLE ON HEAT TREATMENT AT 235* C. FOR 30 SECONDS, THEN SUBJECTING SAID TEXTILE MATERIAL TO A HEAT-SETTING TREATMENT TO INCREASE THE PENETRATION OF SAID DYESTUFF INTO SAID CELLULOSE ACETATE, AND WASHING SAID MATERIAL TO REMOVE SAID THICKENER AFTER THE HEAT-SETTING. 